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Custom Drains

One of OMG's specialties is designing and fabricating custom drains. Though most new and retrofit roof drain installations conform to standard industry practices, there are the occasions when an unusual condition occurs at a drain location. In such instances, the standard drain may need to be modified or customized to fit the particular site conditions.
If you have a special application, or would like a custom design drain, please call 800-633-3800 or download the Custom Drain Submittal Form.

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Product Use

Product Use

OlyFlow RetroDrains are designed to replace existing drains in re-roofing applications. Installed from the roof surface, the OlyFlow RetroDrains are engineered to be installed without removing the existing plumbing or fixture while providing a watertight connection to the roof system and the existing plumbing.


As with all building materials it is the responsibility of the installer to review its usage with a design professional to confirm safety, compatibility and acceptance with the roof cover manufacturer as well as local building codes.

Packaging Information

Packaging Information

Call OMG at 800-633-3800 for a custom order.